Ishioka Noriko ₁ はじめに RI RI RI RI ₂ 悪性褐色細胞腫と治療の現状 3,000 90 I meta- Iiodo-benzylguanidine I-MIBG 1 ₃ α 線の標的アイソトープ治療 2016 6 223 RaCl2 223 Ra 223 Ra 14
表 1 α 線と β 線の違い -decay (42%) Eα = 5.9 MeV At 7.2 h EC (58%) Po 207 Bi 32.9 y EC 516 ms -decay Eα = 7.5 MeV 207 Pb stable EC: 軌道電子捕獲 1 図 1 At 壊変図 表 1 25-50 DNA DNA RBE 0.1 mm RI 4 アスタチン At) ( 8 At 207 207 Pb 図 1 At 7.2 RI RI 5 I-MIBG から へ NET 2 I-MIBG NET 23 I-MIBG I 76 Br meta- 76 Br bromo-benzylguanidine 76 Br-MBBG PET 4 MBBG MIBG MIBG RI 15
I At meta- Atastato-benzylguanidine 6 の治療薬としての評価 At Bi 209 Bi, 2 n At 56 At 28 MeV He 3.5µA 3 160 MBq At At Vaidyanathan G. 5 N-chlorosccusinimide At 図 2 PC12 3 12 PC12 mrna desipramine dl-ne I-MIBG PC12 At, At, NCS, AcOH TFA 70 o C, min Precursor (0.9 µmol) 図 2 合成反応 ( 文献 ) より抜粋 ) 0.2 kbqml I-MIBG I-MIBG 150011,000 I-MIBG 7 24 DNA I-MIBG 500-1,000 PC12 1 0.1 MBq PC12 13612 At 1 g 1 3 図 3 A 1 1 図 3 B At 8 At 60 50 %do ose/g of organ 40 30 20 0 1 h 3 h 6 h 12 h 経過時間 図 3 A PC12 移植マウスにおける 投与後の腫瘍内放射能の経時変化 (n=3)( 文献 ) より抜粋 ) 16
PC12 1 0.56 MBq 1 30 7 14 14 355.8147.6Controlvs. 58.414.1 A-MABG P<0.05 図 4 AB15 At PC12 I-MIBG 9 A-MABG I-MIBG I-MIBG 140 10 I-MIBG 0.56MBq 図 4 C 7 まとめ 1 n %do ose/g of orga 1.0 0.8 0.6 0.4 0.2 0.0 1 h 3 h 6 h 12 h 経過時間 図 3 B PC12 移植マウスにおける 投与後の血中放射能の経時変化 (n=3)( 文献 ) より抜粋 ) 生理食塩水投与 投与 腫瘍 腫瘍 図 4 B 投与 14 日後のマウス写真 ( 文献 ) より抜粋 ) mor volume (% %) Relative tu 00 0 Saline ** * * * ** *** *** We eight (g) 20 15 5 Saline 0 5 15 20 25 30 投与後の経過日数 ( 日 ) 図 4 A PC12 移植マウスにおける 投与後の腫瘍サイズの経時変化, 生理食塩水 (n=4), (n=5), 投与放射能 :0.56MBq/ 匹,*P<0.05,**P<0.01,***P<0.001 ( 文献 ) より抜粋 ) 0 0 5 15 20 25 30 投与後の経過日数 ( 日 ) 図 4 C PC12 移植マウスにおける 投与後の体重の経時変化 ( 文献 ) より抜粋 ) 17
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